Characteristics of myocardial nuclear Ca~(2+)-ATPase after ischemia-reperfusion injury in rats / 第三军医大学学报

Objective To study the regulatory effects of Ca 2+ , ATP, ADP and AMP on myocardial nuclear Ca 2+ ATPase activity after ischemia reperfusion injury Methods The model of myocardial ischemia reperfusion injury was established in rats Myocardial nuclei were purified using sucrose density gradient centrifugation The activity of Ca 2+ ATPase was measured with ascertaining phosphate Results Compared with the control, plasma levels of MDA and FFA after myocardial ischemia reperfusion injury increased significantly ( P

Change of cardiac myocyte nuclear inositol 1,4,5- trisphospate receptor binding proterties in rat with myocardium ischemic reperfusion / 中国药理学通报

Aim Observing the alteration of cardiac myocyte nuclear inositol 1,4,5-trisphosphate receptor (IP_3R)binding proterties in rat subjected to myocardium ischemic reperfusion is to make it clear whether this change is involved in the molecule mechanism of cell apoptosis of rat with myocardial ischemic reperfusion. Method Apoptosis index of myocardial cell was determined using TUNEL assay.Extracting of cardiac myocyte nucleus was accomplished by saccharose density gradient centrifugation method,the binding proterties of nuclear IP_3R in different conditions were detected by radioligand binding assay.Results ①Myocardial cell apoptosis index in rat heart underwent 30 min regional ischemia and 3 h reperfusion was distinctly increased compared with sham-operated group(P

Changes of myocardial nuclear membrane Ca~(2+)-ATPase function in ischemia/reperfusion injury / 中国病理生理杂志

AIM: The changes of myocardial nuclear membrane Ca 2+ -ATPase function was investigated in ischemia/reperfusion injury. METHODS: The model of myocardial ischemia/reperfusion injury was established in rats. Myocardial nuclei were purified with sucrose density centrifugation,the activity of Ca 2+ -ATPase was measured and calcium uptake was assayed with [ 45 Ca 2+ ] . RESULTS: Plasma levels of malondialdehyde (MDA) and free fatty acid (FFA) in myocardial ischemia/reperfusion injury increased significantly( P

Changes in nuclear calcium content and permeability of nuclear pore complex in rat myocardium during ischemia reperfusion injury / 中国病理生理杂志

AIM: To investigate the changes in nuclear calcium content and permeability of nuclear pore complex in rat myocardium during ischemia reperfusion injury.METHODS: The rat model of myocardial ischemia reperfusion injury was established.Myocardial nuclei were purified using sucrose density gradient centrifugation.The nuclear calcium content was measured by atomic absorption spectrophotometer.The permeability of nuclear pore complex was assessed through measuring the amount of calmodulin conjugated Alexa Fluo~(TM) 488 as fluorescent probes transported across nuclear membrane with spectrofluorometer.RESULTS: The nuclear calcium content at 15,30,60,120 and 180 min reperfusion following 30 min sustained ischemia increased 1.31-,1.55-,1.73-,1.94-and 2.14-fold,respectively,as compared with sham-operation group.The permeability of nuclear pore complex at 15 min reperfusion following 30 min sustained ischemia showed no difference from sham-operation group,but it only increased 1.31-,1.38-,1.40-,and 1.48-fold at 30,60,120 and 180 min reperfusion following 30 min sustained ischemia compared with sham-operation group.CONCLUSION: The nuclear calcium content during myocardial ischemia reperfusion injury increases earlier than the permeability of nuclear pore complex does.The increase in the permeability of nuclear pore complex may result in adaptive regulatory effects on nuclear calcium overload to a certain extent during myocardial ischemia reperfusion injury.

Effects of iptakalim hydrochloride on the association and dissociation kinetic processes of [~3H] glibenclamide binding with ATP-sensitive potassium channels in artery smooth muscles and its crosstalk with nucleotides / 中国药理学通报

AIM To investigate the effects of iptakalim hydrochloride(Ipt) on the association and dissociation kinetic processes of [ 3H]glibenclamide(Gli) binding with sulfonylurea receptor(SUR 2B ) of ATP sensitive potassium channel (K ATP ) in vascular smooth muscles derived from Wistar rats,and to compare the properties of Ipt with those of nucleotides. The interactions between Ipt and nucleotides were also determined. METHODS The experiments of the association and dissociation kinetic processes of K ATP blocker[ 3H]Gli binding with endothelium denuded aorta smooth muscles were used. RESRLTS (1)The specific bindings of[ 3H]Gli with SUR 2B were not displaced by Ipt at the concentrations of 10 pmol?L -1 ～ 0 5 mmol?L 1 . Ipt 100 ?mol?L -1 retarded the association kinetic process and accelerated the dissociation kinetic process of [ 3H]Gli binding with SUR 2B . (2)Opposite to Ipt, ATP 1 mmol?L -1 accelerated the association kinetic process and retarded the dissociation kinetic process of [ 3H]Gli binding with SUR 2B There was an interaction between ATP and Ipt in the modulation of [ 3H]Gli binding with SUR 2B . (3) Similar with Ipt, ADP 1 mmol?L -1 retarded the association kinetic process and accelerated the dissociation kinetic process of [ 3H]Gli binding with SUR 2B , there was an interaction between ADP and Ipt in the modulation of [ 3H]Gli binding with SUR 2B . (4)Different from ATP and ADP, UDP had no effect on the association and dissociation kinetic process of [ 3H]Gli binding with SUR 2B . And there was not interaction between UDP and Ipt. CONCLUSION Ipt had no affinity with the binding sites of K ATP blocker in SUR 2B , but had negative allosterical modulation on it. The modulatory properties of Ipt were opposite to those of ATP, similar with those of ADP and different from those of UDP. There were interactions between ATP, ADP and Ipt in the modulation of [ 3H]Gli binding with SUR 2B , but there was not interaction between UDP and Ipt.